/*
 * This software and all files contained in it are distrubted under the MIT license.
 * 
 * Copyright (c) 2013 Cogito Learning Ltd
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

package net.mitza.rel.parser.expression;

import java.util.ArrayList;

/**
 * A base class for AdditionExpressionNode and MultiplicationExpressionNode.
 * 
 * Holds an arbitrary number of ExpressionNodes together with boolean flags.
 * 
 */
public abstract class SequenceExpressionNode extends ExpressionNode {

	/**
	 * An inner class that defines a pair containing an ExpressionNode and a boolean flag.
	 */
	public class Term {

		/** the boolean flag */
		public boolean positive;
		/** the expression node */
		public ExpressionNode expression;

		/**
		 * Construct the Term object with some values.
		 * 
		 * @param positive
		 *            the boolean flag
		 * @param expression
		 *            the expression node
		 */
		public Term(boolean positive, ExpressionNode expression) {
			super();
			this.positive = positive;
			this.expression = expression;
		}

		@Override
		public String toString() {
			return String.format("[%s, %s]", expression, positive ? "P" : "N");
		}
	}

	/** the list of terms in the sequence */
	protected ArrayList<Term> terms;

	/**
	 * Default constructor.
	 */
	public SequenceExpressionNode() {
		terms = new ArrayList<Term>();
	}

	/**
	 * Constructor to create a sequence with the first term already added.
	 * 
	 * @param initialNode
	 *            the term to be added
	 * @param positive
	 *            a boolean flag
	 */
	public SequenceExpressionNode(ExpressionNode initialNode, boolean positive) {
		terms = new ArrayList<Term>();
		add(initialNode, positive);
	}

	public SequenceExpressionNode(ExpressionNode initialNode) {
		terms = new ArrayList<Term>();
		add(initialNode);
	}

	/**
	 * Add another term to the sequence
	 * 
	 * @param node
	 *            the term to be added
	 * @param positive
	 *            a boolean flag
	 */
	public void add(ExpressionNode node, boolean positive) {
		terms.add(new Term(positive, node));
	}

	public void add(ExpressionNode node) {
		terms.add(new Term(true, node));
	}
}
